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Weight Loss Outcomes Following Government-Funded Conversion Gastric Bypass: Roux-en-Y Versus One-Anastomosis-Does the
Chiara Chadwick1,2, George Hopkins1,2, Zoe Jarrott1
1The Royal Brisbane and Women's Hospital, Department of Surgery, Upper Gastrointestinal Surgery Unit, Brisbane, Australia.
Background:
The demand for conversion gastric bypass bariatric procedures has increased; however, the ideal procedure remains contentious, and access to government-funded procedures remains limited. This study aimed to determine if the medium-term weight loss, reflux, and safety outcomes are significantly different in patients who receive conversion Roux-en-Y gastric bypass (RYGB) and One Anastomosis Gastric Bypass (OAGB) in an Australian government-funded hospital (GFH).
Design:
This was a retrospective observational study of 251 adult participants who received conversion gastric bypass surgery at the Royal Brisbane and Women's Hospital between January 1, 2015, and April 30, 2023. The primary outcome measure was the annual percentage total weight loss (%TWL) from 12 months to 5 years following conversion to RYGB versus OAGB. Secondary outcome measures were post-operative reflux, hospital length of stay (LOS), and complications within 90 days.
Results:
The annual median %TWL from 1 to 5 years post-surgery did not demonstrate a statistically significant difference between conversion RYGB and OAGB. Participants who had previously received a laparoscopic adjustable gastric banding (LAGB) and had a conversion to RYGB for gastro-oesophageal reflux demonstrated statistically significantly better annual %TBWL out to 4 years compared to those who had received a prior sleeve gastrectomy (SG) χ 2(1) = 6.4, p = 0.011. Similarly, there was a statistically significant improved %TWL in patients with gastro-oesophageal reflux, who were converted to OAGB from primary LAGB compared to primary SG; however, this was only statistically significant out to 2 years χ 2(1) = 4.2, p = 0.041. Pre- and post-operative gastro-oesophageal reflux and LOS were comparable in conversion RYGB and OAGB procedures. RYGB demonstrated a significantly higher incidence of the post-operative complications out to 90 days; p = 0.008.
Conclusion:
RYGB and OAGB provide durable medium-term weight loss when performed as conversion procedures. Our results suggest that consistent, improved medium-term weight loss can be achieved in participants who undergo conversion gastric bypass in the context of reflux if they have previously received LAGB. There was no significant difference in the incidence of de-novo gastro-oesophageal reflux following either RYGB or OAGB.
